CN106636620A

CN106636620A - Method for reducing SO2 emission in sintering process of iron ore

Info

Publication number: CN106636620A
Application number: CN201611161882.5A
Authority: CN
Inventors: 王海风; 张春霞; 齐渊洪; 严定鎏; 王�锋; 高建军; 郄俊懋
Original assignee: CISRI SHENGHUA ENGINEERING TECHNOLOGY Co Ltd
Current assignee: Linyi Iron And Steel Industry Collaborative Innovation Center; CISRI Sunward Technology Co Ltd
Priority date: 2016-12-15
Filing date: 2016-12-15
Publication date: 2017-05-10
Anticipated expiration: 2036-12-15
Also published as: CN106636620B

Abstract

The invention relates to a method for reducing SO2 emission in a sintering process of iron ore. The intake of S element is reduced from sources, including iron ore, fuel, fluxing agent, return scrap, return mine and water, wherein the S element brought by the iron ore is 30%-40% of the total input; the S element brought by the fuel is 40%-50% of the total input; the sintering flue gas from a sintering machine (A) is divided into two parts according to the emission characteristics; the first part of flue gas is corresponding to a first part air bellow; the temperature of the first part of flue gas is low and the SO2 concentration is low; the second part of flue gas is corresponding to a second part air bellow; the temperature of the second part of flue gas is high and the SO2 concentration is high; after the first part of flue gas exchanges heat with the second part of flue gas, an active coke method is adopted for removing the SO2; for the second part of flue gas, a present desulphurization method can be utilized to remove SO2. Compared with a common sintering process, the method has the advantages that SO2 is reduced by above 25%, the investment is reduced and the present sintering process can be improved.

Description

One kind reduces Ore Sintering Process SO2The method of discharge

Technical field

The present invention relates to Ferrous Metallurgy SINTERING TECHNOLOGY field, more particularly to a kind of to reduce Ore Sintering Process SO2 rows The method put.

Background technology

Based on blast furnace-converter " long flow process ", sintering is the main production process of blast furnace raw material to steel production in China, sintering Ore deposit accounts for the 70～75% of blast furnace burden, and the development to China's steel and iron industry is particularly important.But impact of the SINTERING PRODUCTION to environment Also very big, not only pollutant kind is more, and discharge capacity is big, including smoke-dust, SO2, NOx, fluoride, heavy metal, bis- Evil English etc., is one of main operation of Air Pollutant Emission in integrated iron and steel works.According to statistics, China's sintering circuit in 2013 Smoke-dust discharge capacity is 189085.47 tons, and SO2 discharge capacitys are 557962.14 tons, and NOx discharge is 260697.43 tons, respectively Account for 40.9%, 76.3% and the 47.6% of China's Key Iron And Steel total emission volumn.As can be seen here, sintering circuit smoke pollution The comprehensive regulation of thing is the key that steel industry is reduced discharging.

At present, sinter type smoke pollutant removal technology species a lot, but be mostly the end treatment for Single Pollution thing Technique, such as electrostatic precipitator, sulfur removal technology (including calcium method, magnesium processes, ammonia process), denitrating technique etc., it is non-due to sintering exhaust gas volumn Chang great, about 3000～4000m3/t, and the pollutant levels such as SO2 and NOx are relatively low, cause the investment running cost of end treatment equipment With very high, and it is less efficient.With China in 2012《Steel sintering, pelletizing industrial air pollution thing discharge standard》 (GB28662-2012) issue, it is tighter to sintering flue gas pollutant emission request, reach pollutant only by end treatment Discharge standard, not only technology is difficult, and cost is also very high.In addition, pollutant kind requirement is more, NOx and two is increased The emission limit of Evil English, for bioxin, current China is also without ripe industrialized unit to its effective process.

In sum, belong to the end treatment facility of single function the control method of sintering flue gas pollutant at present more, with Increasing for pollutant kind restriction, end treatment facility is difficult to meet emission request, and its investment operating cost is very high, because This, needs are started with from process control, develop significantly more efficient sintering process energy-saving and emission-reducing technique.

The content of the invention

In order to achieve the above object, the method is comprised the following steps：

A kind of method for reducing Ore Sintering Process SO2 discharges, from source bringing into for S elements, including iron ore, combustion are reduced Material, flux, return expect, return mine, water.Wherein iron ore brings the 30%-40% that S amount of element accounts for general input into, and fuel brings S into Amount of element accounts for the 40%-50% of general input, while the sintering flue gas of sintering machine (A) is divided into into two portions according to discharge characteristics Point：Part I flue gas correspondence Part I bellows, this partial fume temperature is low, and SO2 concentration is low；Part II flue gas correspondence the Two part bellows, this partial fume temperature is high, and SO2 concentration is high；After by Part I flue gas and Part II flue gas heat exchange, can use Activated coke method removes SO2 therein or directly discharges；Part II flue gas can remove SO2 using existing sulfur method.

Further, the heat exchange is exchanged heat using board-like or pipe heat exchanger.

Further, 27 bellows are disposed with from sintering machine entrance to outlet, entrance starts the 1-16 bellows and is Part I bellows, share the first flue, behind 17-27 bellows be Part II bellows, share the second flue；First flue It is arranged in parallel with the second flue, flow of flue gas is in opposite direction, after making Part I flue gas and Part II flue gas heat exchange, using work Property burnt method remove SO2 therein or directly discharge, the second flue removes the existing sulfur method of Part II flue gas utilization SO2。

Further, about 80 DEG C of the Part I flue-gas temperature, about 250 DEG C of the temperature of Part II flue gas, by two Partial fume exchanges heat, and Part I flue-gas temperature is about 150 DEG C.

Further, below 0.07%, below 0.9%, flux contains S for fuel amount control containing S for iron ore amount control containing S Amount control returns mine the amount control containing S below 0.03% below 0.3%, and the amount control containing S of return material is below 3%.

Further, sinter mixture amount control containing S is below 0.08%.

Further, below 0.04%, below 0.5%, flux contains S for fuel amount control containing S for iron ore amount control containing S Amount control returns mine the amount control containing S below 0.01% below 0.1%, and below 1%, total S is input into the amount control containing S of return material Amount control is in below 200g.

Further, sinter mixture amount control containing S is below 0.05%.

Further, the fuel is coke powder and/or coal dust.

Further, it is sintering electro-precipitating dust, blast furnace gravitational dust, blast furnace cloth bag ash, slag and/or steel rolling oxidation to return material Iron sheet.

Further, after by Part I flue gas and Part II flue gas heat exchange, SO2 therein can be removed with activated coke method Or directly discharge；Part II flue gas can remove SO2 using existing sulfur method.

Compared with the conventional method, the beneficial effects of the present invention is：1st, reduction SO2 is brought into by reducing S elements from source Generate.2nd, using sintering process feature, take flue gas segmentation from heat exchange mode, reduce exhaust gas volumn, flue-gas temperature is improved, using existing There are SCR techniques, reduce SO2 discharges, compared with ordinary sinter technique, reduce more than 25%, reduce investment, can be due to existing sintering Technological transformation.

Specific embodiment

Certain factory's sintering specific embodiment

Raw material iron ore, fuel, flux, return material, the index returned mine and see the table below 1-3

The iron ore of table 1, fuel, solvent main component (mass percent, %)

Table 2 is returned mine main component (mass percent, %)

Composition	TFe	SiO₂	CaO	Al₂O₃	MgO	S
							Content	56.03	5.00	9.75	2.57	1.30	0.023

Table 3 returns material main component (mass percent, %)

Above-mentioned raw materials are carried out into dispensing and obtains sinter mixture, be shown in Table 4

The sinter mixture main component of table 4 (mass percent, %)

Reduce S elements from source to bring into, including iron ore, fuel (coke powder, coal dust), flux, return expect, return mine, water. Wherein iron ore brings the 30%-40% that S amount of element accounts for general input into, and fuel brings S amount of element into and accounts for general input 40%-50%, while the sintering flue gas of sintering machine (A) is divided into into two parts according to discharge characteristics：Part I flue gas correspondence Part I bellows, this partial fume temperature is low, and SO2 concentration is low；Part II flue gas correspondence Part II bellows, this part cigarette Temperature degree is high, and SO2 concentration is high；After by Part I flue gas and Part II flue gas heat exchange, can be removed with activated coke method therein SO2；Part II flue gas can remove SO using existing sulfur method₂.Sinter each bellows smoke discharge amount and temperature is shown in Table 5.

Table 5 sinters each bellows smoke discharge amount and temperature

1-16# bellows mix, the mixing of 17-27# bellows, and Gas Parameters are shown in Table 6-1 and table 6-2 after mixing.

Gas Parameters I after table 6-1 mixing

Gas Parameters II after table 6-2 mixing

Two kinds of gases can be using pipe type heat transfer or plate-type heat-exchange, and temperature is 150-160 DEG C after heat exchange

27 bellows are disposed with from sintering machine entrance to outlet, entrance starts the 1-16 bellows for Part I wind Case, share the first flue, behind 17-27 bellows be Part II bellows, share the second flue；First flue and the second flue It is arranged in parallel, flow of flue gas is in opposite direction, after making Part I flue gas and Part II flue gas heat exchange, is removed using activated coke method SO2 therein is directly discharged, and the existing sulfur method of Part II flue gas utilization is removed SO2 by the second flue.

Using above-mentioned sintering process, the SO compared with ordinary sinter₂Discharge reduces 30%.

The above, the only present invention preferably specific embodiment, but protection scope of the present invention is not limited thereto, Any those familiar with the art the invention discloses technical scope in, the change or replacement that can be readily occurred in, All should be included within the scope of the present invention.

Claims

1. it is a kind of to reduce Ore Sintering Process SO₂The method of discharge, it is characterised in that：Bringing into for S elements is reduced from source, including Iron ore, fuel, flux, return expect, return mine, water.Wherein iron ore brings the 30%-40% that S amount of element accounts for general input into, Fuel brings the 40%-50% that S amount of element accounts for general input into, while by the sintering flue gas of sintering machine (A) according to discharge characteristics It is divided into two parts：Part I flue gas correspondence Part I bellows, this partial fume temperature is low, SO₂Concentration is low；Part II Flue gas correspondence Part II bellows, this partial fume temperature is high, SO₂Concentration is high；By Part I flue gas and Part II flue gas After heat exchange, SO therein can be removed with activated coke method₂Or directly discharge；Part II flue gas can be de- using existing sulfur method Except SO₂。

2. it is as claimed in claim 1 to reduce Ore Sintering Process SO₂The method of discharge, it is characterised in that：From sintering machine entrance to Outlet is disposed with 27 bellows, and entrance starts the 1-16 bellows for Part I bellows, shared first flue, behind the 17-27 bellows are Part II bellows, share the second flue；First flue is arranged in parallel with the second flue, flow of flue gas direction Conversely, making after Part I flue gas and Part II flue gas heat exchange, using activated coke method SO therein to be removed₂Or directly arrange Put, the existing sulfur method of Part II flue gas utilization is removed SO by the second flue₂。

3. reduction Ore Sintering Process SO according to claim 1 and 2₂The method of discharge, it is characterised in that：Described first About 80 DEG C of partial fume temperature, about 250 DEG C of the temperature of Part II flue gas, by two parts flue gas heat exchange, Part I flue gas Temperature is about 150 DEG C.

It is 4. according to claim 1 and 2 to reduce the method that Ore Sintering Process SO2 is discharged, it is characterised in that：Iron ore contains Below 0.07%, below 0.9%, flux amount control containing S is returned mine containing S below 0.3% for fuel amount control containing S for S amount controls Amount control is returned and expects the amount control containing S below 3% below 0.03%.

It is 5. according to claim 4 to reduce the method that Ore Sintering Process SO2 is discharged, it is characterised in that：Sinter mixture The amount control containing S is below 0.08%.

It is 6. according to claim 4 to reduce the method that Ore Sintering Process SO2 is discharged, it is characterised in that：Iron ore is measured containing S Below 0.04%, below 0.5%, flux amount control containing S is returned mine containing S amounts below 0.1% for fuel amount control containing S for control Control returns material amount control containing S below 1% below 0.01%, and total S input controls are in below 200g.

It is 7. according to claim 4 to reduce the method that Ore Sintering Process SO2 is discharged, it is characterised in that：Sinter mixture The amount control containing S is below 0.05%.

8. the reduction Ore Sintering Process SO according to claim 4 or 5₂The method of discharge, it is characterised in that：The fuel For coke powder and/or coal dust.

9. the reduction Ore Sintering Process SO according to claim 4 or 5₂The method of discharge, it is characterised in that：Returning material is Sintering electro-precipitating dust, blast furnace gravitational dust, blast furnace cloth bag ash, slag and/or steel rolling iron scale.

10. the reduction Ore Sintering Process SO described in claim 4 or 5₂The method of discharge, it is characterised in that：By Part I cigarette After gas and Part II flue gas heat exchange, SO therein can be removed with activated coke method₂Or directly discharge；Part II flue gas can profit SO is removed with existing sulfur method₂。